react-native/ReactKit/Base/RCTLog.h

// Copyright 2004-present Facebook. All Rights Reserved.

#import "RCTAssert.h"
#import "RCTRedBox.h"

#define RCTLOG_INFO 1
#define RCTLOG_WARN 2
#define RCTLOG_ERROR 3
#define RCTLOG_MUSTFIX 4

// If set to e.g. `RCTLOG_ERROR`, will assert after logging the first error.
#if DEBUG
#define RCTLOG_FATAL_LEVEL RCTLOG_MUSTFIX
#define RCTLOG_REDBOX_LEVEL RCTLOG_ERROR
#else
#define RCTLOG_FATAL_LEVEL (RCTLOG_MUSTFIX + 1)
#define RCTLOG_REDBOX_LEVEL (RCTLOG_MUSTFIX + 1)
#endif

// If defined, only log messages that match this regex will fatal
#define RCTLOG_FATAL_REGEX nil

#define _RCTLog(__RCTLog__level, ...) do {                                                                                                      \
  NSString *__RCTLog__levelStr;                                                                                                                \
  switch(__RCTLog__level) {                                                                                                                    \
    case RCTLOG_INFO: __RCTLog__levelStr = @"info"; break;                                                                                      \
    case RCTLOG_WARN: __RCTLog__levelStr = @"warn"; break;                                                                                      \
    case RCTLOG_ERROR: __RCTLog__levelStr = @"error"; break;                                                                                    \
    case RCTLOG_MUSTFIX: __RCTLog__levelStr = @"mustfix"; break;                                                                                \
  }                                                                                                                                           \
  NSString *__RCTLog__msg = _RCTLogObjects(RCTLogFormat(__VA_ARGS__), __RCTLog__levelStr);                                                        \
  if (__RCTLog__level >= RCTLOG_FATAL_LEVEL) {                                                                                                  \
    BOOL __RCTLog__fail = YES;                                                                                                                 \
    if (RCTLOG_FATAL_REGEX) {                                                                                                                  \
      NSError *__RCTLog__e;                                                                                                                    \
      NSRegularExpression *__RCTLog__regex = [NSRegularExpression regularExpressionWithPattern:RCTLOG_FATAL_REGEX options:0 error:&__RCTLog__e]; \
      __RCTLog__fail = [__RCTLog__regex numberOfMatchesInString:__RCTLog__msg options:0 range:NSMakeRange(0, [__RCTLog__msg length])] > 0;        \
    }                                                                                                                                         \
    RCTCAssert(!__RCTLog__fail, @"RCTLOG_FATAL_LEVEL %@: %@", __RCTLog__levelStr, __RCTLog__msg);                                                  \
  }                                                                                                                                           \
  if (__RCTLog__level >= RCTLOG_REDBOX_LEVEL) {                                                                                                 \
    RCTRedBox *__RCTLog__redBox = [RCTRedBox sharedInstance];                                                                                    \
    [__RCTLog__redBox showErrorMessage:__RCTLog__msg];                                                                                          \
  }                                                                                                                                           \
} while (0)

#define RCTLog(...) _RCTLog(RCTLOG_INFO, __VA_ARGS__)
#define RCTLogInfo(...) _RCTLog(RCTLOG_INFO, __VA_ARGS__)
#define RCTLogWarn(...) _RCTLog(RCTLOG_WARN, __VA_ARGS__)
#define RCTLogError(...) _RCTLog(RCTLOG_ERROR, __VA_ARGS__)
#define RCTLogMustFix(...) _RCTLog(RCTLOG_MUSTFIX, __VA_ARGS__)

#define RCTLogFormat(...) _RCTLogFormat(__FILE__, __LINE__, __PRETTY_FUNCTION__, __VA_ARGS__)
#define RCTLogFormatString(...) _RCTLogFormatString(__FILE__, __LINE__, __PRETTY_FUNCTION__, __VA_ARGS__)

static inline NSString *_RCTLogPreamble(const char *file, int lineNumber, const char *funcName) {
  NSString *threadName = [[NSThread currentThread] name];
  NSString *fileName=[[NSString stringWithUTF8String:file] lastPathComponent];
  if (!threadName || threadName.length <= 0) {
    threadName = [NSString stringWithFormat:@"%p", [NSThread currentThread]];
  }
  return [NSString stringWithFormat:@"[RCTLog][tid:%@][%@:%d]>", threadName, fileName, lineNumber];
}

// Returns array of objects.  First arg is a simple string to print, remaining args are objects to pass through to the debugger so they are
// inspectable in the console.
static inline NSArray *_RCTLogFormat(const char *file, int lineNumber, const char *funcName, NSString *format, ...) NS_FORMAT_FUNCTION(4,5);
static inline NSArray *_RCTLogFormat(const char *file, int lineNumber, const char *funcName, NSString *format, ...)
{
  va_list args;
  va_start(args, format);
  NSString *preamble = _RCTLogPreamble(file, lineNumber, funcName);

  // Pull out NSObjects so we can pass them through as inspectable objects to the js debugger
  NSArray *formatParts = [format componentsSeparatedByString:@"%"];
  NSMutableArray *objects = [NSMutableArray arrayWithObject:preamble];
  BOOL valid = YES;
  for (int i = 0; i < formatParts.count; i++) {
    if (i == 0) { // first part is always a string
      [objects addObject:formatParts[i]];
    } else {
      if (valid && [formatParts[i] length] && [formatParts[i] characterAtIndex:0] == '@') {
        id obj = va_arg(args, id);
        if (obj) {
          [objects addObject:obj];
        } else {
          [objects addObject:@"null"];
        }
        [objects addObject:[formatParts[i] substringFromIndex:1]]; // remove formatting char
      } else {
        // We could determine the type (double, int?) of the va_arg by parsing the formatPart, but for now we just bail.
        valid = NO;
        [objects addObject:[NSString stringWithFormat:@"unknown object for %%%@", formatParts[i]]];
      }
    }
  }
  va_end(args);
  va_start(args, format);
  NSString *strOut = [preamble stringByAppendingString:[[NSString alloc] initWithFormat:format arguments:args]];
  va_end(args);
  NSMutableArray *objectsOut = [NSMutableArray arrayWithObject:strOut];
  [objectsOut addObjectsFromArray:objects];
  return objectsOut;
}

static inline NSString *_RCTLogFormatString(const char *, int, const char *, NSString *, ...) NS_FORMAT_FUNCTION(4,5);
static inline NSString *_RCTLogFormatString(const char *file, int lineNumber, const char *funcName, NSString *format, ...)
{
  va_list args;
  va_start (args, format);
  NSString *body =  [[NSString alloc] initWithFormat:format arguments:args];
  va_end (args);
  return [NSString stringWithFormat:@"%@ %@", _RCTLogPreamble(file, lineNumber, funcName), body];
}

#ifdef __cplusplus
extern "C" {
#endif

NSString *_RCTLogObjects(NSArray *objects, NSString *level);

#ifdef __cplusplus
}
#endif

typedef void (^RCTLogFunction)(NSString *format, NSString *str);
void RCTInjectLogFunction(RCTLogFunction func);